The present invention relates to bezels and electromagnetic interference (xe2x80x9cEMIxe2x80x9d) shields for electronic devices, and, in particular, to a combination of features, molded onto a bezel of an equipment enclosure, that fasten the EMI shield to the bezel.
Typically, electronic devices are housed in standardized equipment enclosures. Many equipment enclosures include an outer housing that is supported by an inner rack. The inner rack commonly comprises a substantially rectilinear metal frame including several vertical columns, each provided with a plurality of mounting and alignment holes that permit the mounting of various components to the inner rack.
Many equipment enclosures also include a removable bezel that forms an aesthetic front face for the enclosure. The bezel may also shield internal components from environmental contaminants, such as moisture and dust, as well as shield the environment from noise generated by components within the enclosure. Removing the bezel provides access to components mounted within the enclosures in order to repair, replace, inspect, and perform maintenance tasks on the components.
Many electronic components generate electromagnetic radiation in the radio frequency (xe2x80x9cRFxe2x80x9d) portion of the electromagnetic spectrum. RF-radiation generated by electronics is a common source of environmental electromagnetic interference (xe2x80x9cEMIxe2x80x9d) that may degrade or impair operation of other electronic devices and circuits exposed to the RF-radiation. Increased use of electronic devices, especially mobile electronic devices such as cellular phones, has increased environmental EMI levels. Consequently, EMI shields have been incorporated into equipment enclosures to block EMI from interfering with components within equipment enclosures as well as to shield the environment from EMI generated by components within the enclosure.
Currently, many EMI shields are semi-permanently) attached to bezels using fasteners and expensive and time-consuming post-mold heat-staking steps during the manufacturing process. In addition to EMI-shield attachment being slow and expensive. EMI-shield removal is tedious, and the risk of damage to the bezel is high. Recycling of EMI shield/bezel combinations requires the plastic bezel to be separated from the EMI shield, and is therefore expensive and time-intensive because of the semi-permanent post-mold heat-stake attachments. Attachment of EMI shields by semi-permanent, post-mold heat-staking steps also fails to provide an option for consumers to purchase a bezel assembly without a pre-installed EMI shield. Consumers purchasing electronic devices in a configuration not requiring an EMI shield must still purchase an equipment enclosure pre-assembled with an EMI shield to ensure adequate shielding for future upgrades.
Thus, manufacturers, designers, and consumers of electronic devices have recognized the need for an EMI-shield-retention mechanism that allows for simple, easily detachable attachment of an EMI shield to a bezel.
One embodiment of the present invention relates to a combination of EMI-shield-retention features, molded onto the inside surface of a bezel of an equipment enclosure. The EMI-shield-retention features collectively snap onto an EMI shield containing receiving apertures complementary to the EMI-shield-retention features. The EMI shield is secured to the interior of the bezel, with movement of the EMI shield restricted in six directions: +X, xe2x88x92X, +Y, xe2x88x92Y, xe2x88x92Z and xe2x88x92Z. Movement of the EMI shield is restricted in the four directions of the X and Y axes by three X, Y-retention features, protruding through two holes and one notch cut in the EMI shield. The horizontal louvers of the bezel, along with five additional xe2x88x92Z-retention features, restrict movement of the EMI shield in the xe2x88x92Z direction. Finally, movement of the EMI shield is restricted in the +Z direction by sliding the EMI shield underneath two flanged +Z-retention features on the left edge of the bezel, while two snap-like +Z-retention features on the right edge of the bezel snap over the top surface of the EMI shield.